All living organisms including bacteria, fungi, plants, and mammals have evolved time keeping mechanisms such as circadian clocks to synchronize their internal state to the external environment. Almost every cell in the human body has a molecular clock and these clocks orchestrate daily rhythms in many physiological processes, from sleep patterns to metabolism.
Circadian rhythms are ~24-hour oscillations in gene expression, behavior and physiology that are generated by these clocks. The most common 24-hour rhythm that we are all familiar with is the sleep-wake cycle. The reason we experience jetlag when we travel to a new time-zone is because our internal clocks are not in synchrony with the new environment. In fact, chronic misalignment of clocks to external environment, for example shift work, has been linked to many human diseases, including diabetes, obesity, Alzheimer’s, and Parkinson’s.
A fundamental understanding of how clocks keep time and control various aspects of our behavior and physiology has important implications for human health. Our goal is to understand the fundamental processes of circadian systems at different organizational levels, from molecules and cells and large-scale networks to organismal physiology and behavior.